Historical trends in daily smoking and quitting by relationship status in Norway, 1973-2022.

Aims: This study aims to investigate trends in self-reported daily smoking and quitting by relationship status in 1973-2022.

Methods: Repeated and representative cross-sectional tobacco surveys of the adult population in Norway were analysed in the age group 25-74 years. Logistic regression was used to estimate the adjusted predicted probability of daily smoking and former smoking for persons in a formalised relationship (married or cohabitant) and persons not in a formalised relationship.

Results: Since the 1970s, the decline in daily smoking has been present for men regardless of relationship status, but with more smoking among men not in a relationship from the 2000s onward. For women not in a relationship, daily smoking increased among those not in a relationship from the mid-1980s, surpassing the smoking rate among men in a relationship. From the 1990s, daily smoking was higher in women not in a relationship compared with women in a relationship. In the past decade (2013-2022), the adjusted odds ratio of daily smoking was 0.49 for people in a relationship compared with those not in a relationship.

Conclusions: Downward trends in daily smoking have been substantial the past 50 years, but differences by relationship status persist. Continued monitoring of smoking behaviour at the population level is crucial to uncover which demographic groups are lagging in the last phase of the tobacco epidemic.